The genus Dicrotendipes Kieffer from China, including 8 species, is reviewed. Two new species, Dicrotendipes nudussp. n. and Dicrotendipes saetanumerosussp. n. are described and the male imagines are illustrated; the record of Dicrotendipes fusconotatus (Kieffer) is the first for China. A key to the males of Dicrotendipes in China is given.

The genus [taxon-name: Dicrotendipes] was erected by Kieffer in 1913, with [taxon-name: Dicrotendipes septemmaculatus] (Becker, 1908) as type species. Adults of [taxon-name: Dicrotendipes] have been considered as pests due to large emergences (Frommer and Rauch 1971; Epler 1988), and have been implicated in allergic reactions in humans in Africa (Cranston et al. 1983). The immature stages are found in both lentic and lotic habitats, but are generally more prevalent in lentic situation. So far, there are 102 species recorded around the word.

In this paper, the Chinese material of [taxon-name: Dicrotendipes] is reviewed. Two new species are described, and a key to the Chinese species of [taxon-name: Dicrotendipes] is presented.

Materials and methods

The morphological nomenclature follows Saether (1980). The material examined was mounted on slides, following the procedure outlined by Saether (1969). Measurements are given as ranges followed by the mean, when three or more specimens are measured, followed by the number of specimens measured (n) in parentheses. Specimens are deposited in the College of Life Science, Nankai University, China and College of Life Science, Taizhou University, China.

Abbreviations of parts measured are as follows:

TL Total length, Length of abdomen + length of thorax; Abdomen is measured from the concave anteriomedian margin of segment I to the apex of the gonostylus; the thorax is measured from the posterior margin of the postnotum to the anterior apex of the scutum in lateral view.

[taxon-name: Dicrotendipes flexus] (Johannsen) closely resembles [taxon-name: Dicrotendipes nervosus] (Staeger) in the structure of hypopygium, but can be separated by the apparently disjunct distributions and fewer setae on R and R1, (21−26 in [taxon-name: Dicrotendipes flexus], more than 35 in [taxon-name: Dicrotendipes nervosus]). All examined Chinese specimens comply with the description of Johannsen (1932) and Hashimoto et al. (1981).

Chinese specimens mainly agree with the description of Freeman (1957), but vary in the coloration of the abdomen: the abdomen of the Chinese species is black; while in Freeman (1957), the abdomen is light green and the median of each abdominal tergite black.

The Chinese specimens mainly agree with the description by Epler (1988). According to Epler (1988), there was some variation in the coloration of the wing in [taxon-name: Dicrotendipes pelochloris], from hyaline to dusky brown, or with diffuse brown cloud along R1, R4+5, M, Cu and An. The wings of Chinese specimens are hyaline, without markings. The Chinese specimens are smaller than the specimens described in Epler (1988). Some measured differences between the Chinese specimens and the specimens described by Epler (1988) are shown in Table 2.

The species name is from Latin, saeta, meaning setae, numerosus, meaning numerous, referring to the tergite IX of the species with more than 30 setae, which is unique within the genus.

Remarks.

[taxon-name: Dicrotendipes saetanumerosus] sp. n. closely resembles [taxon-name: Dicrotendipes tamaviridis] Sasa, 1981 in the structure of hypopygium, but the new species [taxon-name: Dicrotendipes saetanumerosus] can be separated from [taxon-name: Dicrotendipes tamaviridis] on the basis of following points: (1) the anal point of [taxon-name: Dicrotendipes saetanumerosus] sp. n. is broad and not expanded apically, but the anal point of [taxon-name: Dicrotendipes tamaviridis] is slender and expanded apically; and (2) the tergite IX in [taxon-name: Dicrotendipes saetanumerosus] sp. n. has more than 30 median setae, while [taxon-name: Dicrotendipes tamaviridis] has nomedian setae and 8−9 setae in the base of anal point.

Distribution.

The species is known from Hubei, Shandong and Zhejiang Province of China.

The wing spots are variable in [taxon-name: Dicrotendipes septemmaculatus]. They may be absent in teneral specimens, and the pair of spots in cell r4+5 is sometimes combined into one spot. The Chinese specimens have one spot in cell r4+5.

Sasa (1981) described this species based on material from Japan and Niitsuma (1995) described the pupae, larvae and adults. Chinese specimens agree with the adult description of Niitsuma (1995). Some measured differences between the Chinese specimens and the specimens described by Niitsuma (1995) are shown in Table 4.

Financial support from the Zhejiang Provincial Natural Science Foundation of China (Y3100486, Y3110395), the National Natural Science Foundation of China (NSFC, grant No. 30570207, J0630963) and Fauna of China (FY120100) are acknowledged with thanks. We also thank Xue Yu for measuring some specimens.

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